As for things to see, definitely Alps. (I'm at work so I'll just drop a bunch of places for You to google out ;) ) Grossglockner Hochalpenstrasse, Stelvio Pass. For easter europe: http://en.wikipedia.org/wiki/Transfăgărășan, is a really nice drive along the coast of Croatia.

Or... You could take direction up north towards Nordcap, see Geiranger Fjord, Lofoten and other wonders of Norway. Maybe if You'll be passing on a weekend then I could join in for a small trip with my SO ;)

Sorry for a messy post, I'm halfway through my first morning coffee ;)

Bikest meeting of Triumph bikers in Europe. Situated in Salzburg around the Mountain Großvenediger you
can enjoy one of the most open-minded meetings and also use the unique surrounding for fantastic bike-tours!

The bigest bike-festival in Europe. Last year there were at all 100.000 bikers from all over the world,
and not only H-D riders! It's placed in Carinthia, a province of Austria, which is famous for many
well-known biker-tours trough the alps. At the festival most people do party very hard,
and you will of course meet a lot of crazy people there

Maybe also very interesting for your tour planing:

The holy bible(s) for many european bikers are two german books, called the Denzel Motorrad-Touren Westalpen &Denzel Motorrad-Touren Ostalpen. There you can find most of the best biker-tours through the alps.
Both books are only in german available, but if you will know which parts of europe you want to visit, maybe I
can give you some good proposals..

I'm currently looking for a semi-cheap bike to buy and tour round on this summer... my only set plan is Ozora festival in hungary! It's mental, if you're into the whole bohemian trance thing, check out last years video on youtube! Just search Ozora festival and it'll pop up :)